1. Statement of the Technical Field
The invention relates to interconnecting electronic interfaces. More particularly, the invention relates to a flexible appliance and related method for orthogonal, non planar interconnections of at least one first electronic interface disposed on a substrate to an associated second electronic interface positioned beneath the substrate. The flexible appliance and related method compensates for variances in height between the first and second electronic interfaces as well as offsets in the horizontal directions.
2. Background of the Invention
It is known in the art to effect a plurality of electrical connections between interfaces such as a first electronic component and a second electronic component. In such applications, such electrical connections involve manually connecting individual interfaces. In a lower level of assembly, interconnects such as individual wires or ribbons are manually formed, and attached to the first interface. At the next level of assembly, interconnects are clipped and connected to the second interface. In the manufacture of a device having multiple interfaces requiring an individual electrical connection therebetween, this process is extremely time consuming and can only be performed manually.
There have been attempts to improve one or more features related to the foregoing electrical connections between electronic interfaces. For example, in U.S. Pat. No. 4,793,814 to Zifcak et al. there is provided an improved connector arrangement disposed between first and second electrical circuit boards. The connector arrangement improves consistency of contact stresses between repeated connector compression/decompression cycles, minimizes deformation of the connector element, simplifies design, provides greater predictability with regard to the effect of temperature and time on performance, and contact pad wiping during compression. The connector arrangement includes an electrically nonconductive support member adapted to be disposed between the circuit boards comprising resilient elastomeric foam material and being compressed when the circuit boards are urged together. A multiplicity of interconnect elements are disposed in the support member, and positioned selectively in the plane of the connector array, with the element body extending through the support member to expose contact pad engagement surfaces adjacent connector array surfaces.
Another example of a known connector arrangement is disclosed in U.S. Pat. No. 6,835,898 to Eldridge et al. In particular, that reference discloses contact structures exhibiting resilience or compliance for a variety of electronic components. The contact structures are formed by bonding a free end of a wire to a substrate, configuring the wire into a wire stem having a springable shape, severing the wire stem, and overcoating the wire stem with at least one layer of a material chosen primarily for its structural (resiliency, compliance) characteristics.
One device known to require interconnecting of multiple first electronic interfaces to associated second electronic interfaces is a sheet antenna array. A sheet antenna array is a phased array communication antenna having wide application in satellite communication, remote broadcasting, or military communication. A sheet array antenna has desirable characteristics including being low cost, light-weight, having a low profile, and mass producibility. A sheet array antenna is typically comprised of multiple planar conductive elements spaced from a single essentially continuous ground element by a dielectric sheet of uniform thickness. Each of the planar conductive elements is interconnected to an associated interface fed in from another location off the sheet. A wire or ribbon is attached to the associated interface, clipped, and connected to the planar conductive element. The wire or ribbon is connected to the first interface and the second interface using a method such as soldering.
In the manufacture of a device having multiple interfaces requiring an individual electrical connection therebetween, this process can be extremely time consuming and doesn't lend itself well to being automated for several reasons. Particularly, it is too difficult and expensive to convert existing automated machinery to perform the multiple steps required to connect the wire or ribbon from the first interface to the second interface when the size of the device exceeds typical working dimensions. In addition, the machinery required for automating the connection of the wire or ribbon to the first interface, clipping the wire, and then connecting the wire to the planar conductive element could put too much pressure on the substrate and the dielectric sheet. The materials comprising the substrate and the dielectric sheet are often compliant and are not strong enough to support the pressure of the machinery. In addition, due to the compliant nature of the dielectric sheet and/or the substrate, the physical distance between these items often varies between interfaces. This is especially problematic considering that the dielectric sheet could be comprised of a foam material.
Further, conventional methods of making the final connection of the wire or ribbons to the first and second interfaces such as automated mass reflow soldering often require pre-heating the first and second interfaces to a high temperature. This necessarily requires the substrate, the dielectric sheet, and any electronic components disposed on the substrate to also be heated to a high temperature. This is especially undesirable since the substrate, dielectric sheet, or electronic components disposed on the substrate could be damaged by the high temperature.
For example, the planar conductive elements can be antenna dipole elements and the interfaces can be antenna feeds from a source disposed beneath the sheet antenna array. Consequently, the antenna feeds must pass through a hole in the sheet and be individually interconnected to the antenna dipole elements. In a sheet antenna array, there could be four antenna feeds that are fed from a source disposed underneath the sheet array. The antenna feeds could pass through a hole in the sheet array and must be individually interconnected to the associated dipole antenna element. Considering that a sheet antenna array can have numerous arrangements of antenna dipole elements and feeds arranged over the expanse of the sheet, the process of individually interconnecting the antenna feeds to the antenna dipole elements is both labor and time intensive. This is generally considered unsatisfactory.
In view of the foregoing, there remains a need for interconnecting at least one or multiple first electronic interfaces disposed on a substrate to an associated second electronic interface positioned beneath the substrate that can be automated to avoid the time and labor intensive process and other disadvantages of the prior art.